Mitochondrial enzymatic activities and root tip respiration in wild type (WT) and mab1-1. Mitochondrial enzymatic activities and root tip respiration in wild type (WT) and mab1-1. A to C, Enzymatic activity of the PDC (A) and SDH (B), and root tip respiration rate (C). Data shown are mean values of three (A, B) and six (C) independent samples, with error representing se. **P < 0.01. D, Selected amino acids showing significantly lower or higher abundance in roots and shoots of mab1-1 compared to the wild type (Col). Plants were grown on plates for 11 d under long-day conditions. Shoots and roots (six biological replicates) were harvested for gas chromatography-mass spectrometry (GS-MS) analysis. Other amino acids and metabolites detected in roots and shoots of mab1-1 and wild-type plants are shown in Supplemental Table S1. Blue boxes and red boxes indicate significantly higher or lower abundance, respectively, in mab1-1. Iwai Ohbayashi et al. Plant Physiol. 2019;180:896-909 ©2019 by American Society of Plant Biologists